The last original Mel's Drive-In restaurant in San Francisco is one step closer to becoming a mixed-use development.

Plans for the 13,834-square-foot site at 3355 Geary Blvd. include demolishing the 1950s-themed diner and constructing a four-story building that includes 23 residential units, 33 parking spaces for cars and more for bicyclists, according to an environmental evaluation application filed with the Planning Department in June.

The department opened an environmental review case for the site Tuesday.

The property where the restaurant initially opened more than 50 years ago changed ownership nearly two years ago for the first time in at least six decades. Gabriel Mendez, a co-owner of the iconic diner, said he has been negotiating a lease with the site's new owner for the ground-level space of the proposed development. Mel's current lease is not up until April 2018.

“Nothing is secured yet, but we're working on it,” Mendez said.

The Richmond location was the second Mel's to reopen in The City — and the only one to reopen in its original spot — after the first batch of Mel's diners closed in 1972. The other locations are on Lombard Street, Van Ness Avenue and Mission Street, and there are three more Mel's throughout Southern California.

The environmental review process typically includes studies on potential impacts of cultural or historical resources, wind, shadows, noise and air quality. A neighborhood outreach effort will also likely be part of the environmental review process.